The boat is equipped with a battery system provided by Torqueedo. Image Credit: Alex Borton
A solar-electric boat has made a voyage of 45 days in North America without backup diesel engines.
The Solar Sal, piloted by owners David and Alex Borton, made its way from Bellingham, Washington to Juneau, Alaska over the summer. The boat is equipped with a battery system provided by Torqueedo, the technology company said in an emailed statement on Wednesday.
"Even on a completely overcast day this time of year, we can travel at 2-3 knots during daylight hours without drawing on our batteries at all," Alex Borton said in the statement.
"With direct sunlight, we can do 5 knots or more all day without any battery use.
"Most of the trip was overcast and it rained a lot.
"Some days we travelled slowly because we had to; other days we travelled slowly and charged the batteries while underway."
The boat averaged 32 nautical miles per day over the trip.
Solar energy is unlikely to be of use as the main source of energy for commercial ships, but arrays of solar panels on ships' decks may be one way of reducing their emissions and fuel bills.